/* a标签伪类 */

.a a {
    font-size: 20px;
}

.a a:link {
    color: salmon;
    /* 未访问的链接 */
}

.a a:visited {
    color: rgb(114, 250, 166);
    /* 已访问的链接 */
}

.a a:hover {
    color: rgb(114, 177, 250);
    /* 鼠标移动到链接上 */
}

.a a:active {
    color: rgb(177, 114, 250);
    /* 选定的链接 */
}


/* input获取焦点 */

.input input {
    width: 200px;
    height: 30px;
    font-size: 28px;
}

.input input:focus {
    background-color: rgb(255, 168, 168);
}


/* hover */

.father {
    position: relative;
    width: 200px;
    height: 150px;
    background-color: rgb(255, 177, 177);
    text-align: center;
    line-height: 150px;
}

.father:hover .son {
    display: block;
}

.son {
    display: none;
    position: absolute;
    bottom: -60px;
    left: 50%;
    margin-left: -50px;
    width: 100px;
    height: 50px;
    border: 5px solid rgb(214, 171, 255);
    color: salmon;
}


/* 伪元素实现小三角 */

.arrow-right {
    margin: 500px auto;
    width: 300px;
    height: 80px;
    background-color: pink;
    padding-left: 20px;
    border-radius: 10px;
    color: #fff;
}

.arrow-right:before {
    background-color: pink;
    content: "";
    display: block;
    width: 0;
    height: 0;
    border-top: 10px solid #fff;
    border-bottom: 10px solid #fff;
    border-left: 20px solid pink;
    position: relative;
    top: 14px;
    left: 300px;
}